no, you cannot. Not everyone can. At least, not in Germany. People pay 60% of their net income to rent while working 40 hours a week. How do you expect the rent to be paid with just 15 hours of work per week in Germany?
Cut it to 15, move to cheaper residence and cut out gadgets, buying useless shit and owning lots of things. This frees up huge chunks of time and creativity and freedom. The freedom you thought you were working towards toiling 40 hours of your life per week.